Process for the single-bath dyeing of cellulose fibers or mixtures thereof with synthetic fibers with water-insoluble azo dyestuffs produced on the fiber by the exhaustion method

ABSTRACT

Process for the single-bath dyeing of cellulose fibers and their mixtures with synthetic fibers with water-insoluble azo dyestuffs produced on the fiber according to the exhaustion method, wherein an aqueous dyebath is allowed to act on the textile material, at room temperature or moderately elevated temperature, which liquor contains, in addition to alkaline substances, sodium nitrite and an anionic dispersing system, the solution or dispersion of at least one component capable of entering into azo coupling and at least one non-diazotized primary aromatic amine in a medium on the basis of a water-miscible organic solvent or solubilizer, and after absorption of the coupling component, the diazotization of the amine and the dyestuff formation by coupling is caused in that acid or acid salts are added to the dyeing bath at room temperature.

' United States Patent Beyer et al.

PROCESS FOR THE SINGLE-BATH DYEING OF CELLULOSE FIBERS OR MIXTURES THEREOF WITH SYNTHETIC FIBERS WITH WATER-INSOLUBLE AZO DYESTUFFS PRODUCED ON THE FIBER BY THE EXHAUSTION METHOD [75] Inventors: Egon Beyer, Niederhofheim,

Hans-Ulrich von der Eltz, Frankfurt am Main; Erich Schuster, Lammerspiel, all of Germany ['73] Assignee: Hoechst Aktiengesellschaft,

Frankfurt am Main, Germany [22] Filed: Mar. 15, 1973 [21] Appl. No.: 341,363

[30] Foreign Application Priority Data Mar. 18, 1972 Germany 2213241 [52] US. Cl 8/21 C; 8/46; 8/169; 8/173 [51] Int. Cl. D06P 3/83 [58] Field of Search 8/21 C, 46, 169, 173, 83

[56] References Cited UNITED STATES PATENTS 2,030,859 2/1936 Drapal 8/46 X 2,845,326 7/l958 Streck 8/46 NOV. 18, 1975 3,000,298 9/1961 Bryant 8/46 X 3,029,122 4/1962 Posselt et al 8/46 OTHER PUBLICATIONS German Auslegeschrift 1,057,559 2 pages, Kirst et al., 4/21/59.

Primary Examiner Donald Levy Attorney, Agent, or Firm-Curtis, Morris & Stafford [57] ABSTRACT Process for the single-bath dyeing of cellulose fibers and their mixtures with synthetic fibers with waterinsoluble azo dyestuffs produced on the fiber according to the exhaustion method, wherein an aqueous dyebath is allowed to act on the textile material, at room temperature or moderately elevated temperature, which liquor contains, in addition to alkaline substances, sodium nitrite and an anionic dispersing system, the solution or dispersion of at least one component capable of .entering into azo coupling and at least one non-diazotized primary aromatic amine in a medium on the basis of a water-miscible organic solvent or solubilizer, and after absorption of the coupling component, the diazotization of the amine and the dyestuff formation by coupling is caused in that acid or acid salts are added to the dyeing bath at room temperature.

3 Claims, N0 Drawings PROCESS FORTHESINGLE-BATH-DY'EING OF CELLULOSE FIBERS OR MIXTURES THEREOF WITH SYNTHETIC FIBERS WITH WATER-INSOLUBLE AZO DYESTUFFS PRODUCED ON THE FIBER BY THE EXHAUSTION METHOD The present invention concerns a process for the single-bath dyeing of cellulose fibers or mixtures thereof with synthetic fibers with water-insoluble azo dyestuffs produced on the fiber by the exhaustion method.

The two-bath dyeing of cellulose fibers according to the exhaustion process with dyestuff components suitable for the formation of insoluble azo pigments on the fiber according to the principle coupling component in the impregnation bath, diazo component in the developing bath is already known for a long'while. German Pat. No. 729,846 describes a process wherein, within the scope of the calico printing of cellulose fihers, both the coupling component and the diazotable primary aromatic amine in one printing paste is printed on the goods together with the sodium nitrite and the az'o dyestuff is then developed by a passage through an acid; A further process is known from German Pat. No. 1,262,957 according to which coupling components are applied on the textile material according to the exhaustion method in a single bath with stabilized dior tet razoamino compounds of primary amines which are resistant to alkalies and the dyestuff is developed on the fiberby adding an acid to the bath.

The present invention is based on the observation that cellulose fibers and their mixtures with synthetic fibers, preferably polyester fibers, can be dyed according to the exhaustion method in a single bath with water-insoluble azo dyestuffs produced on the fiber if an aqueous liquor is allowed to act on the textile material, at room temperature or moderatelyelevated temperature, which liquor contains, in addition to alkaline substances, sodium nitrite and an anionic dispersing system, the solution or dispersion of at least one component capable of entering into azo coupling and at least one non-diazotized primary aromatic amine in a medium on the basis of water-miscible organic solvent or solubilizer and after absorption of the coupling component, the diazotization of the amine and the formation of the dyestuff by coupling on the fiber are then effected by adding acid or acid salts to the dyeing bath at room temperature.

For the practicability of the present invention it is decisive that the primary aromatic amines which are water-insoluble in an alkaline medium are made clearly soluble or prefectly dispersible by means of suitable means in order to keep the dyebaths stable without any precipitations both in the impregnating phase within the alkaline range and in the developing phase within the acid range. This condition is obtained according to the present invention by suitable solvents and a dispersing system which is effective in both process steps.

For preparing the dyeings according to the process claimed there may be considered the coupling components sufficiently known from the ice color technique, those being used according to the present invention which have a substantivity effect towards fibrous material. Such compounds are those which couple in a neighbouring position to a hydroxy group and do not have solubilizing groups, particularly aryl amides of aromatic or heterocyclic o-hydroxycarboxylic acids or acylacetic acids and other aromatic or heterocyclic hydroxyl compounds and compounds containing an enolizable or enolized ketomethylene group in a hetrocyclic ring. Such substances are, for example arylamides of the 2,3-hydroxynaphthoic acid, 2-hydroxyanthracene- 3-carboxylic acid, 4-hydroxydiphenyl-3-carboxylic acid, 2-hydroxy-carbazole-3-carboxylic acid, 3-hydroxydiphenylene-oxide-2-carboxylic acid, 3-hydroxydiphenylene sulfide-2-carboxylic acid, 'acetoacetic acid or benzoylacetic' acid. Furthermore, among other compounds hydroxybenzenes, polyhydroxybenzenes, hydroxynaphthalen es and pyrazolones which may be substituted by non-ionic. radicals proved to besuitable.

As diazonium compounds for developing the am dyestuffs, there can be used according to the present invention all primary aromatic amines which, together with the aforementioned coupling components, yield water-insoluble mono, dis or polyazo dyestuffs,consequently also tetrazonium compounds of aromatic diamines, and likewise the fast color salts which may be obtained by stabilizing the corresponding amines. The amines suitable therefor, including aminoazo dyestuffs do not possess ionic substituents and are known as diazo components from the ice color technique.

The process of the present invention can be applied to the known cellulosic fibers and mixtures of synthetic fibers, for example polyester fibers, and cellulose fibers. Cellulose fibers in question are in this connection native fibers such as flax, hemp, linen and cotton, or regenerated fibers suc'has viscose staple fiber, spun rayon and modal fibers (polynosic type).

The method of working of the new process for dyeing V cellulose fibers and their mixtures is outlined in the following paragraphs. For preparing the dyeing bath the variants of the process specified hereinafter may be applied.

l. Joint solution of the dyestuff components The proposed quantity ofa coupling component (calculated on the desired depth of shade, the substantivity and the liquor ratio) and the quantity of a primary aromatic amine derived therefrom are dissolved with a solvent, particularly a monovalent, aliphatic alcohol having l 4 carbon atoms, for example methanol, ethanol, propanol or butanol, in the presence of sodium hydroxide solution and a small quantity of hot water.

ll. Separate solution of the dyestuff components The proposed quantity of the'coupling component is dissolved in the usual manner according to the cold dissolving method. preferably with ethanol, sodium hydroxide solution and water, without adding formaldehyde. The primary, aromatic amine is separately dissolved in one of the alcohols mentioned sub l) or in another suitable solvent such as dimethyl sulfoxide, dimethyl formamide, diacetone alcohol, dimethyl acetamide, tetrahydrofurfuryl alcohol, glycerin, or methoxy butanol.

This solution or these solutions are stirred into a bath having a temperature of 30C and consisting of soft water, sodium hydroxide solution, sodium nitrite, crystallized disodium phosphate, sodium chloride and, as dispersing agent, the sodium salt of 2,2'-dinaphthylmethane-6,6-disulfonic acid or a mixture of equal parts of oleylmethyltaurine andlignin sulfonate. The latter anionic dispersing agents are also applied after the azo coupling reaction.

The textile material of cellulose fibers is first treated for 30 to 45 minutes at 30C with this bath at a goodsto-liquor ratio of l 10 to l 30 (in an apparatus consisting of open vat and winch vat), the material is then taken out of the bath or the liquor is pumped back into the preparing vessel, and l ml/l of hydrochloric acid of 20B and 0.1 ml/l of acetic acid of 60 strength are added per each 1 ml/l of sodium hydroxide solution of 32.5 7c strength (38 B) total lye). With that the pH of the dyeing bath is adjusted to 5.8 to 6.0 whereby the diazotization of the primary aromatic amine and the coupling to the azo dyestuff sets in simultaneously and is finished within 30 minutes during which the goods are treated at 25 30C.

Note: Although the disodium phosphate prescribed as buffer reacts with the simultaneously present sodium hydroxide solution to trisodium phosphate, it must be used according to this invention. The commercial product crystallized disodium phosphate (dodecahydrate, Na HPO .l2H O) always contains the same quantity of crystal water per mole. From the trisodium phosphate, however, products with varying content of crystal water are available. thus the application of which could cause differences in the pH-range aspired to.

The dyeings are then subjected to a subsequent treatment in the usual manner by a thorough rinsing in cold and hot water and by a soaping at 60C and boiling temperature with sodium carbonate, a detergent and polyphosphate.

The following general instructions for the full shade are valid for the preparation of the dyeings according to the present invention at a goods-to-liquor ratio of l 20:

l. Joint solution (advantageously for amines being pres ent as hydrochlorides) of a coupling component and of a primary aromatic amine are dissolved with of a monovalent. aliphatic alcohol having I 4 carbon atoms.

of soft water of 80C and of sodium hydroxide solution of 32.5% strength (38Be') [1. Separate solution L5 6 ml/l ml/l This solution or these solutions are stirred into an aqueous bath of 30C which contains the further constituents:

ml/l of sodium hydroxide solution of 32.59?

strength. (38Be') of the sodium salt of 2.2'-dinaphthylmethane6 6'-disulfonic acid 3 g/l of oleylmethyltaurine and 3 g/l of lignin sulfonate.

of disodium phosphate. crystallized (dodecahydrate Na HPO lZH O) 2 g/l of crystallized sodium nitrate and I 20 g/l of sodium chloride.

4 For the diazotization and coupling the following acids are added per 1 ml/l of the total amount of lye:

l ml/I of hydrochloric acid of 20Be' and 0.l ml/l of acetic acid of "/1 strength.

Under these conditions the following quantities of acid are theoretically required for the diazotization of primary aromatic amines (fast color bases):

an acid for the neutralization of the alkaline substance from the impregnating bath.

an acid quantity for the formation of the salt of the amine (e.g. hydrochloride) an acid quantity for the formation ofN O (or HNO from the sodium nitrite.

This theoretical total quantity of acid can be calculated since it depends on the given concentrations of base, nitrite and alkaline substance.

In connection with the claimed process it is surprising that the acid quantity required for obtaining the full dyestuff yield, i.e., the complete coupling, is considerably smaller than the theoretically calculated quantity which is reduced because of the fact that the diazonium salt just formed by the diazotization releases a certain amount of acid during the immediately following coupling which is available for further reactions. The balance between diazotized and non-diazotized azo base is continuously shifted by the fact that the diazotized portion of the base is constantly bound by the coupling.

[t was likewise not foreseeable that with the usual (two-bath) coupling the excess-of base used which is relatively high with regard to the theoretical amount can be kept lower according to the process of the present invention. This is due to the favourable pH range near to the neutral point (which results from the acid deficiency) and the more complete coupling resulting therefrom which proceeds considerably faster due to the constantly shifted equilibrium between coupled and non-coupled diazo component.

In this regard there may be mentioned the following a advantages achieved by the present invention: saving of time by faster progress of the dyeing; consolidation of several operations in one process step wherein diazotization and coupling take place simultaneously; saving of the azo base by smaller excesses; higher yield by better utilization of the azo dyestuff forming components.

It could not be expected either that the fastnesses to rubbing of the dyeings thus prepared correspond to the standard of equally full dyeings prepared on the fiber with insoluble azo dyestuffs according to the usual twobath process and are even better in some cases due to the efficiency of the dispersing system claimed which keeps the pigment portion formed outside the fiber in a condition which allows its being rinsed out very easily.

The numbers of the Colour Index indicated in the Examples to characterize the dyestuffs were taken from the 2nd Edition 1956 and the supplemental volume of 1963.

The following Examples serve to illustrate the invention but they are not intended to limit it thereto.

EXAMPLE 1 After an appropriate preliminary treatment by boiling, cross-wound bobbins of cotton were treated for 30 minutes, at a goods-to-liquor ratio of l 20, with an aqueous dyebath of 30C prepared per liter of dyebath as follows:

ml/l of sodium hydroxide solution of 32.5 7n

strength (38Be') and 3 mill of water of 50C and this solution was stirred intoan aqueous bathof 30C which had the following composition:

ml/l of sodium hydroxide solution of 32.5 71 strength of the sodium salt of 2.2'-dinapthylmethane- 6,6'-disulfonic acid of crystallized disodium phosphate,

of crystallized sodium nitrite and of sodium chloride.

After having acted for 30 minutes on the textile material, the dyebath was pumped back into the preparing vessel and ml of hydrochloric acid of B and mill of acetic acid of 60 71 strength were added thereto. The goods were treated for 30 minutes at C with this dyebath having a pH value of about 5.9, the dyed bobbins were then rinsed with cold and hot water, soaped for 15 minutes at 60C 30 and 15 minutes at boiling temperature with an aqueous A full red dyeing having very good fastnesses was obtained.

The following Table gives a summary of further combinations of dyestuff forming components which may be applied according to the dyeing instructions of Example 1 (joint solution), their quantities to be used and the shades obtained therewith on cellulose fibers.

v I r -continued 2 ml/l of water of'SOfC and t 0.3 ml/l of sodium hydroxide solution of 32.571 strength '(38B).(38B),'and' l.5 g/l of the primary aromatic amine of the formula were dissolved in 4.5 ml/l of dimethyl sulfoxide.

Both solutions were then stirred into the same aqueous dyebath as described in Example 1 and the fibrous material was then treated with this bath as described in the same Example, acidified for developing the dyestuff and rinsed with water.

In order to convert the metal-free, red dyeing produced in this manner on the fiber into the corresponding metal complex compound, the goods were treated for 30 minutes at 95C with an aqueous dyebath which had the following composition:

1 g/l of cobalt chloride (CoCl .2l-l O) 5 ml/l of a 7r aqueous solution of sodium nitriloacetate,

3 g/l of sodium carbonate (anhydrous) and 2 g/l ofa reaction product of 1 mole of isotridecyl alcohol and 8'mols of ethylene oxide, and then rinsed hot and thoroughly cold. From the original red dyeing a green shade having very good fastnesses was developed thereby. 4

We claim:

1. A process for the single-bath dyeing of cellulose fibers and mixtures thereof with polyester fibers, with water-insoluble azo dyestuffs produced on the fibers by the exhaust method, comprising the steps of: contacting a textile material containing the said fibers, at room temperature or moderately elevated temperature, with an aqueous dyebath containing, an alkaline substance,

TABLE Coupling component Example 2 l 5 g/l Azoic Coupling Component 35-C.l. 37 6l5 Example 3 1.5 g/l 28-0]. 37 54l Example 4 1.5 g/l 8-C.l. 37 525 Example 5 1.5 g/l 23-C.l. 37 555 Example 6 1.5 g/l 4-C.l. 37 560 Example 7 L5 g/l l3-C.l. 37 595 Example 8 1.5 g/l l5-C.l. 37 600 Primary aromatic amine Example 2 l g/l Azoic Diazo Component 32-C.l. 37 090 Example 3 L2 g/l 2-C.l. 37 005 Example 4 1.5 g/l 32-C.l. 37 090 Example 5 1.2 g/l 3-C.l. 37 010 Example 6 L5 g/l 46-C.l. 37 080 Example 7 L5 g/l ll-C.li 37 085 Example 8 l g/l 46-C.l. 37 080 Shade yellow orange scarlet red claret bluish black brown EXAMPLE 9 Hank yarn of cotton was dyed for 30 minutes on hank dyeing machine, at a goods-to-liquor ratio of 1 20, with an aqueous dyebath prepared per liter volume as follows:

1 g/l of the compound Azoic Coupling Component l2- C.l.-No. 37 550 was dissolved with a mixture of 3 ml/l of ethanol.

3. A process as recited in claim 1, wherein the primary aromatic amine is dissolved in an aliphatic, monovalent alcohol having from one to four carbon atoms or diacetone alcohol, dimethyl sulfoxide, dimethyl acetamide, dimethyl formamide, tetrahydrofurfuryl alcohol, glycerine or methoxy butanol and the said coupling component is dissolved in an aliphatic, monovalent alcohol having from one to four carbon atoms, said alco hol containing sodium hydroxide and a small quantity 

1. A PROCESS FOR THE SINGLE-BATH DYEING OF CELLULOSE FIBERS AND MIXTURES THEREOF WITH POLYESTER FIBERS, WITH WATER-INSOLUBLE AZO DYESTUFFS PRODUCED ON THE FIBERS BY THE EXHAUST METHOD, COMPRISING THE STEPS OF: CONTACTING A TEXTILE MATERIAL CONTAINING THE SAID FIBERS, AT ROOM TEMPERATURE OR MODERATELY ELEVATED TEMPERATURE, WITH AN AQUEOUS DYEBATH CONTAINING, AN ALKALINE SUBSTANCE, SODIUM NITRITE, AN ANIONIC DISPERSING SYSTEM COMPRISING THE SODIUM SALT OF 2,2''-DINAPHTHYL-METHANE-6, 6''-DISULFONIC ACID OR LIGNIN SULFONATE IN MIXTURE WITH OLEYLMETHYL TAURINE, A SOLUTION OR DISPERSION OF AT LEAST ONE COMPOUND CAPABLE OF ENTERING INTO AZO COUPLING AND AT LEAST ONE NON-DIAZOTIZED PRIMARY AROMATIC AMINE IN A WATER-MISCIBLE ORGANIC SOLVENT OR SOLUBILIZER; AFTER ABSORPTION OF THE COUPLING COMPONENT UPON THE FIBERS, EFFECTING DIAZOTIZATION OF THE SAID AMINE AND FORMATION OF THE DYESTUFF BY COUPLING, BY ADDING ACID OR ACID SALTS TO THE DYEBATH AT ROOM TEMPERATURE; AND AGAIN CONTACTING SAID FIBERS WITH SAID ANIONIC DISPERSING SYSTEM COMPRISING THE SODIUM SAKLT OF 2,2''-DINAPHTHYL-METHANE6,6''-DISULFONIC ACID OR A MIXTURE OF LIGNIN SULFONATE WITH OLEYLMETHYL TAURINE.
 2. A process as recited in claim 1, wherein an aliphatic, monovalent alcohol having one to four carbon atoms is used as the solvent for the coupling component and the primary aromatic amine, said alcohol being used in the presence of sodium hydroxide and a small quantity of water.
 3. A process as recited in claim 1, wherein the primary aromatic amine is dissolved in an aliphatic, monovalent alcohol having from one to four carbon atoms or diacetone alcohol, dimethyl sulfoxide, dimethyl acetamide, dimethyl formamide, tetrahydrofurfuryl alcohol, glycerine or methoxy butanol and the said coupling component is dissolved in an aliphatic, monovalent alcohol having from one to four carbon atoms, said alcohol containing sodium hydroxide and a small quantity of water. 